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    SubjectRE: [PATCH 9/10] drivers/scsi/megaraid: Use DIV_ROUND_UP
    Julia,

    Frame_count is the major parameter used by our megaraid sas FW. It may cause some issues after this change. Please keep the original implementation.

    Thanks.

    Bo Yang

    -----Original Message-----
    From: Julia Lawall [mailto:julia@diku.dk]
    Sent: Saturday, August 02, 2008 11:16 AM
    To: DL-MegaRAID Linux; linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org; kernel-janitors@vger.kernel.org
    Subject: [PATCH 9/10] drivers/scsi/megaraid: Use DIV_ROUND_UP

    From: Julia Lawall <julia@diku.dk>

    The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
    (d)) but is perhaps more readable.

    An extract of the semantic patch that makes this change is as follows:
    (http://www.emn.fr/x-info/coccinelle/)

    // <smpl>
    @haskernel@
    @@

    #include <linux/kernel.h>

    @depends on haskernel@
    expression n,d;
    @@

    (
    - (n + d - 1) / d
    + DIV_ROUND_UP(n,d)
    |
    - (n + (d - 1)) / d
    + DIV_ROUND_UP(n,d)
    )

    @depends on haskernel@
    expression n,d;
    @@

    - DIV_ROUND_UP((n),d)
    + DIV_ROUND_UP(n,d)

    @depends on haskernel@
    expression n,d;
    @@

    - DIV_ROUND_UP(n,(d))
    + DIV_ROUND_UP(n,d)
    // </smpl>

    Signed-off-by: Julia Lawall <julia@diku.dk>

    ---
    drivers/scsi/megaraid/megaraid_sas.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff -u -p a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
    --- a/drivers/scsi/megaraid/megaraid_sas.c
    +++ b/drivers/scsi/megaraid/megaraid_sas.c
    @@ -1615,7 +1615,7 @@ static int megasas_create_frame_pool(str
    * Calculated the number of 64byte frames required for SGL
    */
    sgl_sz = sge_sz * instance->max_num_sge;
    - frame_count = (sgl_sz + MEGAMFI_FRAME_SIZE - 1) / MEGAMFI_FRAME_SIZE;
    + frame_count = DIV_ROUND_UP(sgl_sz, MEGAMFI_FRAME_SIZE);

    /*
    * We need one extra frame for the MFI command

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